RT-PCR was used to examine expression of transgenic rat SF-1 in lines 7, 14, and 15 (A). For each line, the rat transcript was amplified using RNA from tissues isolated from trans-genic (indicated as +) or negative littermate (indicated as –) animals. Samples are heart (Hr), kidney (K), liver (L), lung (Ln), spleen (S), stomach (St), testis (T), ovary (O), adrenal (A), pituitary (P), and hypothalamus (H). RNase protection analysis was used to measure mRNA levels in transgenic lines 7 and 14 (B). SF-1 and actin transcript levels were measured using their respective, specific RNA probes. The SF-1 probe distinguished rat and mouse transcripts by protecting distinct sized mRNAs. Controls are shown in lanes 1–4 and are as follows: 1, tRNA with probes to both SF-1 and actin; 2, rat testis RNA with SF-1 probe; 3, mouse testis RNA with SF-1 probe alone; 4, mouse testis RNA with actin probe. RNA isolated from tissues noted above the lanes of transgenic mice (indicated as +) or negative littermates (indicated as –) was assayed for both SF-1 and actin mRNAs. The lanes are as follows: 5, line 14 transgenic mouse testis; 6, negative mouse testis; 7, line 14 transgenic mouse ovary; 8, negative mouse ovary; 9, line 7 transgenic mouse testis; 10, line 7 negative mouse testis; 11, line 7 transgenic mouse ovary; 12 line 7 negative mouse ovary; 13, line 7 transgenic mouse adrenal; 14, line 7 negative mouse adrenal. Arrows show protected fragments for transgenic rat SF-1 (rSF-1), endogenous mouse SF-1 (mSF-1), and actin.